1. Field of the Invention
A mobile or stationary modular, self-contained dehydration toilet and gray water recovery system and method that include a dehydration engine made part of the toilet or installed remotely for efficiently processing human waste from multiple toilets and used in conjunction with a mobile or stationary platform for the recovery and recycling of gray water.
2. Description of Related Art
Due to the global population growth and severe droughts causing water shortages, there is a critical demand to efficiently process human waste without using natural resources such as fresh water and/or electricity generated from burning oil or coal. Employing toxic chemicals is not a safe alternative. Another demand for efficient human waste treatment and gray water recovery is based on the extreme mobility of large numbers of people resulting from the movement of armies throughout the world, refugee camps, or during recovery from natural disasters. Low power consuming dehydration toilets and gray water recovery systems that are portable or stationary are desirable for solving the processing of human waste not only in industrialized countries but also in developing nations.
Many types of portable toilets are shown in the prior art. Some of these toilets make use of electro-coagulation to flocculate and remove oils, suspended solids, and heavy metals from domestic and industrial wastewaters. The electro-coagulation process utilizes a controlled electric current that is passed through wastewater, often from electrolytic plates, which in turn charges particles in the wastewater (including particles smaller than one micron) that coagulate. The coagulated particles flocculate to form a mass that either floats on the surface or settles to the bottom depending upon the nature of the compounds that have coagulated together. Once the flocculated particles are floating or have settled to the bottom, they may be removed. Electro-coagulation is an extremely effective and cost-efficient method for treating wastewater in that it does not require the use of chemicals, pathogens and other microorganisms are killed, most contaminants are removed from the wastewater, and the operating costs are low.
U.S. Pat. No. 6,719,894, issued Apr. 13, 2004 to Gavrel, et al., describes a process for the electro-coagulation of waste fluids. Pressurized wastewater is passed between charged electrolytic plates to form precipitate particles of organics, particulates, and metal contaminants. The water and particulates then pass from the reactor vessel into a floatation chamber where dissolved gases cause the precipitate particles to float to the surface for removal to create a clarified waste water.
U.S. Pat. No. 6,746,593, issued Jun. 8, 2004 to Herbst, describes a high volume electrolytic water treatment system and process for treating wastewater. In that invention, solids are removed from the wastewater which is then passed into a tank containing electro-coagulation electrodes that destabilize materials such as fats, oils, greases, and surfactants. Electro-coagulation of the wastewater causes contaminants to flocculate and float to the surface. The foam and floating sludge is removed by a foam removal apparatus and the clarified water is discharged after passing over an effluent weir and out of a clear water discharge tube.
U.S. Pat. No. 4,209,389, issued Jun. 24, 1980 to Hartkorn, describes a method using bacteria for removing pathogenic microbes and dissolved organic contaminants from wastewater liquids. The first stage of the described process involves removing substantially all colloidal materials using electro-coagulation. Thereafter, specifically chosen microorganisms are added to the wastewater to remove the remaining organic contaminants.
U.S. Pat. No. 4,999,930, issued Mar. 19, 1991 to Kishi, et al., shows a device that dries raw sewage. This system uses a plurality of beat balls which are paddled around to provide some dehydration of sewage. The system requires an inefficient array of chemical elements in an attempt to dehydrate waste materials.
U.S. Pat. No. 5,152,074, issued Aug. 6, 1992 also to Kishi, et al., shows a similar device that utilizes conductive heating as the heating elements.
U.S. Pat. No. 5,218,724, issued Jun. 15, 1993 to Blankenship, shows an incinerator toilet with a removable catalyst container. One of the drawbacks of this device is that it uses pellets for reducing odor which are inserted and removed for replacement.
U.S. Pat. No. 5,276,924, issued to Hachima on Jan. 11, 1994, shows a method and apparatus for disposing of body waste that includes inductive heating.
U.S. Pat. No. 6,101,638, issued to Hammond on Aug. 15, 2000, shows a toilet that utilizes air pressure, grinding and heat to produce a dry powder waste. A second patent, U.S. Pat. No. 6,496,988 issued to Hammond on Dec. 24, 2002, shows a compact recycling electric dehydration toilet. While both of these patents describe a useful method and system for treating human waste that is self-contained, it is believed the energy consumption is higher than desirable especially in mobile and self-contained environments.
Water, the most essential element to human life, is one of the largest natural resources polluted with human waste. In the industrialized countries, each toilet flush uses between four to seven gallons of water except where the 1.6 gallon flush toilets have been mandated. On average a typical household uses over 40,000 gallons of water each year just to flush their toilet. Lakes and oceans are being inundated with large volumes of partially and, sometimes not, treated human waste that has polluted many areas of the world. Problems with portable toilets typically include consumption of large amounts of energy in boiling water over a small surface area and failure to break down body fats inherent in human feces that can be thirty percent or more oils and fats preventing a true dry dehydrated powder as the residue. The amount of electrical power drawn per flush in some portable toilets is high—in some cases in excess of 3 KW per flush. The present invention described herein overcomes the above problems by providing an energy efficient way to dehydrate and sanitize human waste.
In addition to the consumption and subsequent pollution of water supplies inherent with using traditional toilets and the inefficiencies with respect to moving human wastes, there is also a large amount of gray water created from all types of washing that makes the water unsuitable for human consumption. Gray water contains detergents and other wastes, such as those found in wastewater from car washes, washing machine discharge, showers and sinks. The large volume of gray water is also a critical item in portability as it relates to the consumption and post-processing of water in vehicles such as boats and recreational vehicles as well as in stationary applications such as residential, commercial and industrial structures. Certain areas of the United States have chronic water supply problems and drought that requires a very controlled use of water volume. Developing nations have communities that have water shortages and a lack of sanitary sewer systems that result in disease and death.
The present invention overcomes many of the problems that have been found in stationary or portable toilets and in the overall problems addressing gray water and its recovery for reuse.